Hello. Have Calcell HF500.2 amp (2*500Wt@2Ohm).
Worked nice about 2 years (1*alpine SWR12, then 2*Alpine SWR12 bridged) but then suddenly "fried". I replace 8 transistors in PS (irfp044) and then amp reborn and worked well for one week...
Then strange thing started. Shaking amp (when driving) caused loud BUMP from subs. We tried to kick amp slightly - it work as drum
But it works well, when it's is in "normal" conditions (not shaking\ striking).
Ok. Opened this again and noticed some strange things:
1. One of secondarie's wire is torn and there arent about 2cm of this... I'm afraid it can short to others, yes? What to do? Repair with piece of wire and isolate? Just isolate? Or It's so serios, tht only tranformer rewiring will help?
2. When I replace transistors, the area about this was black dust, like after fire, but all part were ok, so I just cleaned them. But I also noticed, that transformer's wires were "filled with laque\dielectric" (I thougt...). But maybe it is just MELTED laque\dielectriс from wires?
3. I checked resistance between secondaries and main - it seems ok (not shorted). But who knows ok this or not when amp is
Hope You will give usefull advices and comments, thank You.
Here are some photos:
http://radikal.ru/F/i024.radikal.ru/0911/8e/d0d5313c6c63.jpg
http://radikal.ru/F/i057.radikal.ru/0911/2a/f4f553028279.jpg
http://radikal.ru/F/s52.radikal.ru/i138/0911/f9/dce4e52264e0.jpg
Worked nice about 2 years (1*alpine SWR12, then 2*Alpine SWR12 bridged) but then suddenly "fried". I replace 8 transistors in PS (irfp044) and then amp reborn and worked well for one week...
Then strange thing started. Shaking amp (when driving) caused loud BUMP from subs. We tried to kick amp slightly - it work as drum
But it works well, when it's is in "normal" conditions (not shaking\ striking).
Ok. Opened this again and noticed some strange things:
1. One of secondarie's wire is torn and there arent about 2cm of this... I'm afraid it can short to others, yes? What to do? Repair with piece of wire and isolate? Just isolate? Or It's so serios, tht only tranformer rewiring will help?
2. When I replace transistors, the area about this was black dust, like after fire, but all part were ok, so I just cleaned them. But I also noticed, that transformer's wires were "filled with laque\dielectric" (I thougt...). But maybe it is just MELTED laque\dielectriс from wires?
3. I checked resistance between secondaries and main - it seems ok (not shorted). But who knows ok this or not when amp is
Hope You will give usefull advices and comments, thank You.
Here are some photos:
http://radikal.ru/F/i024.radikal.ru/0911/8e/d0d5313c6c63.jpg
An externally hosted image should be here but it was not working when we last tested it.
http://radikal.ru/F/i057.radikal.ru/0911/2a/f4f553028279.jpg
An externally hosted image should be here but it was not working when we last tested it.
http://radikal.ru/F/s52.radikal.ru/i138/0911/f9/dce4e52264e0.jpg
An externally hosted image should be here but it was not working when we last tested it.
Perry Babin,
After I twist, push, pull it, resistance drop to 0 or 100-200 ohms and then rising slowly (???).
Here is my short video with measuring results:
YouTube - Calcell hf500.2 repair issue
It's shorted trafo, right?
After I twist, push, pull it, resistance drop to 0 or 100-200 ohms and then rising slowly (???).
Here is my short video with measuring results:
YouTube - Calcell hf500.2 repair issue
It's shorted trafo, right?
Last edited:
Do You mean something like this?
http://radikal.ru/F/s55.radikal.ru/i150/0911/a0/c8584354a137.jpg
Now I see only "1" on DMM !
Do you think, I can fix toroid and windings with hot glue, isolate those wire pieces and use this?
http://radikal.ru/F/s55.radikal.ru/i150/0911/a0/c8584354a137.jpg
An externally hosted image should be here but it was not working when we last tested it.
Now I see only "1" on DMM !
Do you think, I can fix toroid and windings with hot glue, isolate those wire pieces and use this?
Last edited:
Yes, like that.
If you cannot get it to go to near 0 ohms now, it may be good enough to use as it is. I wouldn't worry about the single open conductor. It's not ideal but it shouldn't cause any problems. If you have epoxy, brush a thin layer over the windings in that area. I wouldn't use hot glue. Make absolutely sure that you cannot make it short again before applying the epoxy.
If it fails again and a replacement isn't available, then you can re-wind it.
If it has four 25 amp fuses (or whatever it has), you may want to reduce them to four 10 amp fuses and drive around with it a day or so (listening at low to moderate volume) to make sure that there are no other problems. This will help protect the power supply FETs if there is another short. If it's OK for a day or two, you can go back to the original fuses.
If you cannot get it to go to near 0 ohms now, it may be good enough to use as it is. I wouldn't worry about the single open conductor. It's not ideal but it shouldn't cause any problems. If you have epoxy, brush a thin layer over the windings in that area. I wouldn't use hot glue. Make absolutely sure that you cannot make it short again before applying the epoxy.
If it fails again and a replacement isn't available, then you can re-wind it.
If it has four 25 amp fuses (or whatever it has), you may want to reduce them to four 10 amp fuses and drive around with it a day or so (listening at low to moderate volume) to make sure that there are no other problems. This will help protect the power supply FETs if there is another short. If it's OK for a day or two, you can go back to the original fuses.
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